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Water Calculations/Conservation/Sanitation

Our water capacity is the overall limiting factor of the number of days we can stay at sea. As pointed out below, we carry enough water for 17 days assuming 3 liters/day/person and 4 crew members. We can stay out for 26 days assuming 2 liters/day/person, which is 'doable' in a pinch. Note: The return crew can carry up to 50 gallons more in 10 additional 5 gallon collapsible containers.

 

Water Usage

• Daily ration for each person is 3 liters.

• VQ has two water tanks for potable water: 40 gallons to Port and 15 gallons to Starboard (208 liters).

• We will always draw from the 15 gallon tank.

• When it is empty, we can refill it from the 40 gallon tank.

• The 40 gallon tank selector under the floorboards must always remain off unless transferring to the 15 gallon tank. Failing to shut this valve off can cause the top 15 to 20 gallons to drain through the foot pump faucet when on port tack.

• Always use the salt water foot pump to wash dishes. Thereafter you can give them a fresh water 'spritz' from the spray bottle.

• The tank water is for drinking only, not for cooking, dishes, cleaning or hygiene.

• If you want to use some fresh water for hygiene, it must come from your own water bottle as part of your daily 3 liter allotment.

• Coffee & tea also comes from your 3 liter allotment.

• We can refill the tanks in a good rain using our awning rainwater collection system.

• Assuming no rain, we have enough drinking water for 208 liters/(3liters/person * 4 people) = 17 days which is how long it will take us to get to the Azores assuming we make 110nm/day. This distance translates into an average speed of 4.6 knots. Therefore, if our sailing speed dips below 4.6 knots and we are behind our goal distance; we should motorsail at as low an rpm as possible to get our speed into the six+ knot range.

• If we fall more than 10% below our overall goal distance and have not replenished our water, rationing will be implemented (2.5 liters/day/person).

• If we fall more than 20% below our overall goal and have not collected any water, we move to 2.0 liters per day.

• Rationing can also be guaged by the weather reports for wind, rain, etc.

Other Water

• We will have plastic water jugs for cooking and 'spritzing' the dishes, counter, and head with the spray bottles. Up to 1 gallon per day for this purpose = 17 gallons (we will have filled 26...roughly 10 extra)

• 10 extra gallons for 'extra rations', which is enough for almost 5 more days at 2liter/person/day

• Hand pump desalinator for 'extreme emergency rations'

• Awning that can catch water & refill the tanks when it rains

• VQ carries 10 more 5 gallon collapsible water jugs for supplementary water on the trip home. This will give the return crew the capacity for 50 extra gallons if they think that they will need it.

Sanitation

• Crew should fill their water bottles from the fresh water foot pump. These water bottles have a charcoal filter in them that is good for roughly 150 refills. VQ carries 10 spare filters for the water bottles. Each bottle holds 22 fluid ounces = .66 liter. Therefore, each bottle can be refilled 4.5 times/day. Filters should be replaced every 30 days or so.

• When you fill the 40 gallon tank, add roughly 1 teaspoon of bleach for every 10 gallons you add if you expect the water quality is questionable. If the water is really 'rank' add 2 teaspoons for every 10 gallons.

• When the 15 gallon tank is empty, refill it from the 40 gallon tank.

• The filters in our water bottles will filter out the bleach taste and any extra 'stuff' that the bleach may have missed.

• Boiling water for 3 to 5 minutes is the only absolute method to 'kill' everything. This should be done if water is going to be used on open wounds or other medical purposes (if you have the time)

 

Treating Water with a 5-6 Percent Liquid Chlorine Bleach Solution (no colors or fragrence)
Volume of Water to be Treated	Treating Clear/Cloudy Water: Bleach Solution to Add	Treating Cloudy, Very Cold, or Surface Water: Bleach Solution to Add
1 quart/1 liter	3 drops	5 drops
1/2 gallon/2 quarts/2 liters	5 drops	10 drops
1 gallon	1/8 teaspoon	1/4 teaspoon
5 gallons	1/2 teaspoon	1 teaspoon
10 gallons	1 teaspoon	2 teaspoons

DOH Pub 821-031

 

Conversions

1 liter = .26 gallons

1 gallon = 3.8 liters

1 fluid ounce = .03 liter